Explosion venting construction



p 1964 w. G. ROBRECHT ETAL 3,150,749

EXPLOSION vemrmc CONSTRUCTION 4 Sheets-Sheet 1 Filed May 15, 1961INVENTOR) Ill/807? 6. ROJR H 7' ROD/VI) E. HRIST/4N P 1964 w. G.ROBRECHT ETAL 3,150,749

EXPLOSION VENTING CONSTRUCTION 4 Sheets-Sheet 2 Filed May 15 1961INVENTORS rV/lEl/k a. xoaxscur Byeaawsrz. ewe/$77.4

A T'TOR/VII'S Sept. 29, 1964 w. G. ROBRECHT ETAL 3,150,749

EXPLOSION VENTING CONSTRUCTION Filed May 15, 1961 4 Sheets-Sheet 3 INTORJ' waaux axe 56H? flaw/var z. cum/arm Y Sept. 29, 1964 w. G. ROBRECHTETAL 3,150,749

EXPLOSION VENTING CONSTRUCTION 4 Sheets-Sheet 4 Filed May 15, 1961INVENTORS rwzaa s. 20442-01;- eoalvzv 5. cMP/s'r/n/v ATTORNEY-S UnitedStates Patent "cc 3,150,749 EXPLOSION VENTING CONSTRUCTIQN Wilbur G.Robrecht, Grosse Pointe Woods, Mich, and

Rodney E. Christian, 2780 Middlebury Lane, Birmingham, Mich; saidRobrecht assignor to Parke, Davis & Company, Detroit, Mich, acorporation of Michigan Filed May 15, 1961, Ser. No. 109,984 18 Claims.(Cl. 189-64) This invention relates to explosion venting of buildings orother structures, and more particularly to an improved windowconstruction for quickly venting a building when the pressure within thebuilding reaches a predetermined abnormal value, as in the case ofexplosions occuring within the building, in order to avoid humancasualties and property damage.

It is particularly desirable that adequate provision be made for ventingexplosions from a building in which flammable solvents and otherhazardous materials are utilized in operations carried on in thebuilding. The present invention solves this problem by the provision ofwindows in the perimeter walls of the building so constructed andmounted as to rapidly relieve, via the window openings, abnormalpressures resulting from an explosion occurring within the building.

Another object of the present invention is to provide a windowconstruction which is operable to relieve abnormal pressures within abuilding up to a predetermined value without removal of or damage to thewindow panels, and which also prevents air from being fed back into thebuilding via the window openings after return to normal pressureconditions.

A further object is to provide a weather resistant explosion ventingwall consrtuction which is inexpensive to manufacture and install.

Still another object is to provide a window construction of the abovecharacter which provides rapid venting of the building in spite of theaccumulation of snow and ice in the window openings.

A still further object is to provide a window construction of the abovecharacter which is easily changed to vent explosions of varying force sothat the pressure specification of a particular area of the building isdeterminable by the pressure specification of the particular windowconstruction installed therein.

Yet another object is to provide a window construction of the abovecharacter which is self-sealing in the window opening against normalinternal pressures up to a predetermined value but which permits rapidventing of the building when the pressure exceeds such value.

In the accompanying drawings:

FIG. 1 is a fragmentary elevational view of the outer side of a precastconcrete wall section provided with window openings and enclosed bywindow panels in accordance with the present invention.

FIG. 2 is a fragmentary elevational view of the inner side of a portionof the concrete wall section of FIG. 1.

FIG. 3 is a cross sectional view taken on the line 33 of FIG. 2.

FIG. 4 is a fragmentary perspective view illustrating one of the windowopenings of the concrete wall section.

FIG. 5 is a fragmentary enlarged perspective view of a window stop ofthe invention for holding the window panels in place in the windowopenings.

FIG. 6 is a fragmentary enlarged perspective view illustrating a windowpanel inserted in a sealing gasket also provided in accordance with theinvention.

3,156,749 Patented Sept. 29, 1964 FIG. 7 is a fragmentary crosssectional view taken on the line 77 of FIG. 2.

FIG. 8 is a vertical cross sectional view on the line 8-8 of FIG. 2.

FIG. 9 is a fragmentary view of a portion of FIG. 8 enlarged toillustrate details thereof.

FIG. 10 is a vertical cross sectional view corresponding to FIG. 8 butillustrating a venting position of the window construction during anexplosion.

FIG. 11 is an enlarged fragmentary view of a portion of FIG. 10.

FIG. 12 is a fragmentary horizontal cross sectional view taken on theline 12-12 of FIG. 8.

FIG. 13 is a fragmentary horizontal cross sectional view taken on theline 1313 of FIG. 10.

FIG. 14 is a fragmentary elevational view of a modified form of windowwall construction also in accordance with the invention.

FIG. 15 is a vertical cross sectional view taken on the line 15-15 ofFIG. 14.

FIG. 16 is a horizontal cross sectional view taken on the line 16-46 ofFIG. 14.

FIG. 17 is an elevational view of a window gasket utilized in theexposion venting window wall construction of FIG. 14.

FIG. 18 is an enlarged fragmentary perspective view of the lower righthand corner of the gasket of FIG. 17.

FIG. 19 is an enlarged fragmentary perspective view of the lower righthand comer of the window wall construction of FIG. 14.

FIG. 20 is a vertical cross section view corresponding to FIG. 15 butillustrating a venting position of the window construction during anexplosion.

FIG. 21 is an enlarged fragmentary cross sectional view corresponding tothat of FIG. 16 but illustrating a venting position of the window panelat the middle of one side edge thereof during an explosion.

Referring to FIG. 1, portions of three prefabricated reinforced concretewall sections 20 are shown from the outer side thereof, each of which ispreferably of a size to contain several generally rectangular windowopenings 22. Between adjacent window openings the prefabricated sectionsconstitute a series of vertically extending ribs 24, and a series ofhorizontally extending ribs 26. The concrete sections 20 are arrangedside by side and in tiers, one above the other, and secured in positionto form a complete structural wall by the usual methods of unitingprefabricated concrete sections.

The shape of ribs 24 and 26 which define the contour of the individualwindow openings 22 are best seen in FIGS. 3 and 4. These ribs aretapered so as to provide smooth vertical and horizontal marginal walls28 and 30 respectively which converge slightly as they extend inwardlyfrom the outer side of the wall section. The corners of the windowopenings are shown rounded as at 32 for purposes of illustration.Marginal walls 28 and 30 terminate at the intersection thereof with aflange 34 which extends around the inner portion of window opening 22 toprovide marginal window stop surfaces consisting of top and bottomshoulders 35 and side shoulders 38. The side shoulders 38 are outwardlycurved to provide a convex stop surface. The top and bottom shoulders 36extend straight across the opening but are undercut or inwardly taperedso as to extend flush with the outwardly curved side shoulders 38 (FIG.8).

Each of the window openings 22 is adapted to be closed by a closurepanel 40 made of non-fragile, resiliently flexible material such asplastic and are manufactured as flat sheets of generally rectangularform with rounded corners. Closure panels 40 are suitably dimensionedand have suflicient elasticity so that they are bendable into a convexform to fit within window openings 22 complemental to the shoulders 36,38 of the peripheral concrete flange 34. The plastic selected is onethat has suitable light transmitting and heat insulating properties.Also, the plastic must be resistant to shock so as to withstand theeffect of explosive forces as well as the impact encountered when thepanel is ejected from its mounting in window opening 22 and falls to theground. One material found suitable for the above purpose isfiberglassreinforced polyester plastic.

As best seen in FIGS. 2, and 8, the means provided for securing plasticpanels 4t) to the concrete sections includes a flexible window stop 42preferably made of weather resistant neoprene. This material is extrudedso as to have a cross sectional shape in the relaxed condition thereofindicated by the broken line showing in FIG. 5. Stop 42 is resilientlyexpandable by flexing it to the cross sectional shape indicated in solidlines in FIG. 5. Window stops 42 thus comprise: a back wall 44 adaptedto fit against the vertical inner surface of Window ribs 26; top andbottom walls 46 which fit snugly against the inclined surfaces offlanges 34; reversely bent leg portions 43 extending from the innersides of walls 46 which fit against shoulders 36 of the window opening;and foot portions 53- extending outwardly from each leg portion 4-8 andwhich rest against the top and bottom marginal walls of the windowopenings. Each foot portion 50 of stop 42 is recessed to provide aretaining groove 52 therein for mounting closure panel 40. Each stop 42is suitably cut to length so that it extends along the inner verticalsurface of rib 26 between, but not into, the rounded corners 32 ofwindow openings 22.

Referring to FIGS. 3 and 6, a sealing gasket 54 comprising an endless,generally tubular member is fitted around the marginal edges of closurepanel 49 to assist in obtaining a weather tight closure of windowopening 22. Gasket 5% has a solid portion 56 with a slot 58 therein toreceive the peripheral edges of closure panel with a snug fit. A hollow,bulbous portion 5 is integrally joined to the inner side of solidportion 56 of gasket 54, the wall of bulbous portion 58 having athickness approximately half that of the lips of solid portion 56 tothereby provide an easily deformable weather strip. Gasket 54 ispreferably made of weather resistant neoprene and is extruded so thatthe cross sectional shape of bulbous portion 53 thereof when relaxed isgenerally circular, as shown in FIGS. 6 and 13.

To install the above described window construction in the windowopenings 22 of concrete wall section 20, the foot portions it) ofresilient window stops 42 are pulled away from one another so that theycan be passed from inside the wall over the flanged portions 34 ofhorizontal window rib 26. The foot portions of the stop are thenreleased, allowing them to snap against the Window opening wall surfaces30, and allowing leg portions 48 of the stop to draw up against theundercut shoulders 36. The resiliency of window stop 42 is then sufiicient to hold it in place without the use of adhesives or otherfastening devices. However, for those wall surfaces 30 located at theends of concrete wall section 20, window stop 42 is cut longitudinallyin half and each half is affixed in place by bonding or otherwisefastening back wall portion 44 of the stop to the vertical insidesurface of rib 26.

The sealing gasket 54 may be assembled onto closure panel 40 at thefactory, and then this sub-assembly shipped flat to the job site. Eachclosure panel 40 while in the flat, relaxed condition thereof isinserted in a window opening 22 from the outside of the wall section.The bottom edge of the panel, with gasket 54 attached thereto, isinserted into groove 52 of window stop 42 so that sealing gasket 54 istightly bottomed in groove 52 (FIG. 9). The flat panel is then boweduntil the upper edge of panel 44 is in position to be pushed inwardlyand inserted in groove 52 of window stop 42 at the top of window opening22 (FIG. 8). The dimensions of panel 40 with gasket 54 mounted thereonare such that it is bowed outwardly even after being fitted between thetop and bottom stop grooves 52. Since panels made of the aforesaidfiberglass-reinforced polyester plastic are elastic, the bowing createsa tension in the panel tending to straighten it out. This force in turnpushes foot portions 50 of the window stops 42 tightly against the wallsurfaces 30 and also serves to hold the bulbous portion 58 of sealinggasket 54 against the outwardly curved side shoulders 38 of the windowopening (FIG. 12).

With the window closure panel 40 so installed, and under flexingtension, the window opening 22 is sealed against external wind loads.Such loads tend to further seal the window opening by pressing the panelinwardly to further squeeze the bulbous portion 58 of the window gasketagainst shoulders 36 and 38. The convex shape of the window panelprovides high strength against external wind loads. Since such loadstend to straighten the panel, the top and bottom edges of the panelexert compression loads on the foot portions 50 of the stops 42 so thatthey are pressed against wall surfaces 30. Hence wind load stresses aretaken by the concrete ribs 26 so that there is no tendency of panel 40to rip loose from its mounting in the stops 42. The bulbous portion 58of sealing gasket 54, due to its resiliency and deformability, generallyconforms to uneven edges and bends in shoulders 36 and 38 of the windowopening. Also, in the round corners 32 located between the ends of stop42 and the respectively adjacent side shoulders 38 the bulbous portion58 overhangs the upper edge of shoulder 36, as shown in FIG. 7 andindicated 55 in FIG. 3, to thereby assist in sealing against externalpressure.

When the internal pressure of the building is slightly superatmospheric,as is often the case in air conditioned buildings where the interiorpressure may exceed the exterior pressure by about /2 inch of water, thesealing gasket 54 also functions to prevent escape of air from thebuilding. This results from such air pressure acting against theremaining hollow portion of bulbous portion 58 which extends inwardly ofthe window opening beyond the edges of shoulders 36 and 38, the airpressure tending to squeeze such portion down so that it continues tooverlay or overhang the edges of shoulders 36, 38, thereby providing aself-sealing action. If panel 40 tends to pull slightly away from sideshoulders 36 under such light pressure, the flexibility of bulbousportion 58 of the sealing gasket causes it to expand towards its normalshape so that window opening remains sealed. From the foregoing it willbe appreciated that window stops 42 cooperate with the flexed windowpanels 40 and the bulbous sealing gasket 54 to provide a permanentwindow closure resistant to displacement and weather under all ordinarycircumstances.

However, the primary purpose of the window c011- struction of thepresent invention is to permit outward release of interior air pressureWhenever there are abnormal conditions which require sudden venting ofthe interior of the building as a safety measure. Due to the bowed formof closure panel 40, an abnormally high pressure against the inside facethereof tends to further increase the bowing effect and consequently toassist in the ejection of the panel from window opening 22. With thisarrangement the plastic panel 40 is readily ejected whenever the gaseouspressure on the concave side is in excess of a predetermined blow-outvalue, such as 20 to 30 lbs. per square foot. The panel will thereuponbe expelled through the outwardly flaring window opening 22 in thebuilding wall section 2%) and will fall harmlessly to the ground.However, for minor explosions.

creating pressures between the superatmospheric pressure previouslymentioned and the aforesaid blow-out pressure, a pressure relievingventing action occurs without window panel 40 being pulled loose fromits mounting.

This venting action is best understood by comparing the position of thewindow structure in FIGS. 10, 11 and 13 during a minor explosion withthe position of the window structure in FIGS. 8, 9 and 12 during normalconditions. Whenever the gaseous pressure on the concave side of thepanel 40 is within the above range, the panel is pushed outwardly andbows slightly further while still being retained in grooves 52 of windowstop 42. As shown in detail in FIG. 11, in this venting position the legportion 48 of stop 42 has pulled away from the undercut shoulder 36 andthe foot portion 50 has been pulled off the window wall surface 30.Actually, a hinging action occurs wherein the resilient leg and footportions 48 and 50 flex or pivot about the upper edge of the undercutshoulder 36. At the same time, the resiliency of the gasket 54,particularly the bulbous portion 58 thereof, causes it to expand ingroove 52 of the window stop as the groove itself expands due to theflexing action. Hence the frictional retaining fit between sealinggasket 54 and stop 42 is maintained to prevent the panel from pullingloose from grooves 52 until the blow-out pressure is reached.

Tln's hinging action of the window stop allows the side edges of panel40, together with the bulbous portion 58 of gasket 54 attached thereto,to pull away from the outwardly curved side shoulders 38 (FIGS. and 13)so that the air under pressure can escape between the bulbous portions58 of the gaskets and the surfaces of shoulders 38, and then out alongthe side marginal window walls 28. It is to be noted that suflicientclearance is provided between the side edges of panel 40 and side walls28 to permit such venting, and that the taper of walls 28 enlarges thisclearance as the panel moves outwardly in the window opening. Hence,immediate pressure release is obtained for pressures within said rangewithout panel 40 coming loose from stop 42. It has been found that assoon as the pressure drops back to normal panel 40 pops back into itssealed position indi: cated in FIGS. 8 and 9 thereby providing an eventighter and better fit of the window stop and sealing gasket against thewindow shoulders 36 and 38.

In addition to the concrete framing system illustrated in FIGS. 1-13,the invention can be readily adapted for use with other conventionalframing systems, one of which is illustrated in the embodiment of theinvention disclosed in FIGS. 14-21.

Referring to FIG. 14, a portion of a conventional steel or aluminum sashwindow wall is shown comprising vertical and horizontal frame members 70and 72 joined at right angles to one another to provide a rectangularlyframed window opening. As shown in FIGS. 15, 16 and 19, frame members 70and 72 of the sash are T-shaped in cross section and have flanges 71 and73 respectively which extend into the window opening in the planethereof to define the outline of the opening. Each window opening isenclosed by a closure panel 74 which is manufactured and installed as aflat window panel. Panel 74 is preferably made of the same material aspanel 40 of the previous embodiment although a rigid but non-breakablematerial may also be used.

Panel 74 is mounted in a rectangular sealing and mounting gasket 76(FIG. 17) which is in turn mounted on flanges 71 and 73 of sash framemembers 70 and 72. Gasket 76 is preferably made of a resilient material,such as weather resistant neoprene, and is an assembly of two resilientwindow stop strips 78 bonded at right angles to a pair of sealing strips80, here shown respectively as the horizontal and vertical members ofgasket 76.

Referring to FIG. 18, the horizontal window stop strip 78 is extruded soas to have a generally S-shaped cross section providing a groove 82 toreceive sash frame flange 73 and another groove 84 to receive the edgeof closure panel 74 (FIGS. 15 and 19). The vertical sealing strip 88 isextruded to have a hollow cross section similar to that of sealinggasket 54 previously described, thereby providing a resilientlydeformable bulbous portion 86 shown in FIG. 18 in the normal relaxed,expanded condition thereof. Sealing strip also has a groove 88 whichsnugly receives the vertical flange 71 of frame member 70 (FIGS. 18 and19).

Window gasket 76 may first be installed in place on the sash framemembers 7'8 and 72 and then the flexible closure panel 74 installed ingasket 76. The lower edge of panel 74 is inserted in groove 84 of lowerstop strip 78 and then the panel is bowed outwardly so that the upperedge thereof can be inserted into groove 84 in the opposite, upper stopstrip 78. Panel 74 will then pop inwardly to the flat condition, therebystretching the resilient stop strips 78 and sealing strips 88 in avertical direction. This interference fit of panel 74 in gasket 76insures a tight fit of the metal sash flanges 73 in grooves 82 of thetop and bottom stop strips 78 and helps hold panel 74 in grooves 84 ofstop strips 78. As illustrated in FIG. 19, the bulbous portion 86 ofsealing strip 80 is squeezed flat by the window panel to provide aweather resistant seal along the vertical side edges of the windowopening.

The installation sequence may be altered so that gasket 76 is firstassembled to panel 74 and then this panelgasket assembly installed inthe sash frame. Should a rigid rather than flexible panel be used, thenthe resiliency of sealing strips S0 becomes especially helpful instretching gasket 76 onto the panel. A gasket adapted for use with arigid panel should preferably fit taut on the panel but not so tight asto interfere with the resilient action of stop strips 78 describedbelow.

In operation, explosive forces within 'a predetermined range of valuesexert pressure on the inside face of panel 74, causing it to bowoutwardly into a concave configuration so that the vertical side edgesof the window panel are thereby pulled away from sealing strips 88. Thewindow stop strips 78 operate with a hinging action as illustrated inFIG. 20 so that panel 74 can flex away from sealing strips 80 withoutbeing pulled out of stop strips 78. This allows a venting action tooccur between the side marginal portions of panel 74 and the bulbousportion 86 of sealing strip 80 (FIG. 21). If panel 74 is made rigidrather than elastic the venting action is similar except that theoutward movement of the panel results primarily from the hinging andstretching of stop strips 78 rather than from the combined flexingeflect of the stop and panel.

Of course, as in the previous embodiment, when the explosive forceresults from a major explosion and therefore exceeds the maximumblow-out pressure for which stop strips 78 are designed, panel 74 isextracted from grooves 84 and ejected as a unit from the window openingin order to relieve the pressure of the major explosion.

It is to be understood that, without departing from the presentinvention, the concave-convex bowing action of the flexible panels 40and 74 may be in directions other than the vertical direction shownherein, provided corresponding changes are made in the cooperatingwindow opening shoulders and window stops. Moreover, by utilizingmaterials of different resiliency in panels 40 and 74 and in windowstops 42 and 78, by varying the depth of panel retaining grooves 52 and84 and/or the amount of material provided in foot portions 54 of stops42 and around groove 84 of stop strip 78, the aforesaid pressurerequired to eject the window panels from the window openings can becorrespondingly varied as desired. Thus the blow-out pressurespecifications can be varied from one area of the building to another bythe simple expedient of installing window stops designed to meet thepressure specifications of the particular building area withoutmodifying the window wall or sash framing construction.

For example, in the window construction of FIGS. l13, a blow-outpressure of about to lbs/sq. in. may be obtained when constructedaccording to the following:

Closure panel Approximately 19 X 13 /8" x Material-fiberglass-reinforcedpolyester plastic such as that sold under the trademark Glasbord by theKemlite Corporation of Joliet, Illinois Window stop 42- Thickness ofwalls 44, 46 and 48%" Depth of groove 5Zabout Width of groove 52about AAngle of undercut shoulder 36 from vertical30 Slope of window wall 30-4Material-neoprene, Durometer Gasket 54- Depth of slot 58about Thicknessof solid portion 56- Bulbous portion 58 X /2" X Length of gasket 5454"Materialneoprene, Durometer 60 The invention provides a simple andinexpensive weather resistant window construction which also permitsexplosion release through the window walls, thereby eliminating the needfor other equipment to meet the explosion venting requirements ofinsurance underwriters and building code authorities for structureswhich utilize flammable solvents and other hazardous materials in theiroperation. In addition, immediate explosion release is obtained, and inthe case of minor explosions, without expelling the window panels. Thisin turn eliminates the cost of re-installing blown out panels after suchan explosion, and equally important, prevents air from feeding to a firewhich often results after such an explosion.

We claim:

1. In a building having a window opening therein provided with at leasttwo pairs of opposite edges, the combination of a window panel closingsaid opening, a pair of panel engaging members extending along a firstpair of corresponding opposite edges of the window opening and thepanel, said panel engaging members having each a first portion securelyattached to the first pair of edges of the window opening and aresilient second portion movably connected to said first portion andhaving a groove therein for receiving the corresponding edge of thepanel, said second portions of said panel engaging members normallyretaining the panel against the second pair of edges of the windowopening but being movable relative to said first pair of edges of thewindow opening in a direction outwardly of the window opening whileretaining said opposite edges of the panel in gripped relation in saidgrooves to permit the panel to move bodily outwardly away from saidsecond pair of window edges, said second portions being suflicientlydistortable to release the edge of the panel from said groove inresponse to an abnormally high pressure acting outwardly against theinner face of the panel.

2, In a building the combination of a window opening having outwardlyfacing shoulders at opposite edges thereof against which a window panelis adapted to be positioned for closing the opening, a pair of windowstops extending along said opposite edges of the window opening, each ofsaid stops being formed at least in part of a resiliently flexiblematerial and having one portion thereof engaged over said shoulder toretain the stop in the Window opening against outward displacement andhaving a second portion engaging the outer face of said shoulder toretain the stop against inward displacement, said second portion havinga groove therein for receiving an edge of the window panel, meansforming a resilient CPL hinge connecting said first and second portionsof said window stop and a window panel having opposite edges engaged insaid grooves of said stops.

3. The combination called for in claim 2 wherein the remaining edgeportions of said panel are seated against other outwardly facingshoulders provided around the window opening and said remaining edgeportions are unobstructed in a direction outwardly of the plane of thewindow.

4. In a wall having a pair of spaced apart and parallel frame meanspartially defining a window opening and having further frame meansproviding spaced apart window stop surfaces defining the remainder ofthe window opening, a pressure venting window assembly for said openingincluding in combination, window stop means mounted along each of saidparallel frame means and including a resiliently flexible portion havinga groove therein disposed on the side thereof facing the outer side ofthe wall, and a non-fragile window panel dimensioned to close saidwindow opening and having a pair of spacedapart edge portions eachreceived in one of said grooves to thereby retain said panel in thewindow opening with marginal portions thereof adjacent said window stopsurfaces, said resiliently flexible portion of said stop means beingmovable relative to the remainder of said stop means to permit movementof said edge portions of said panel while being retained in said grooveswhereby said panel is movable in response to abnormal gaseous pressuresof less than a predetermined blow-out value acting against the innerface of the panel to thereby rapidly relieve said pressure via the spacecreated by such panel movement between said window stop surfaces and themarginal portions of said panel adjacent thereto without therebyejecting the panel from the window opening, said resiliently flexibleportions being adapted to grip said panel edge portion received thereinwith a force suflicient to retain the panel in the groove until gaseouspressures acting on the inner face of the panel equal or exceed thepredetermined blow-out value whereupon the panel is pulled out of saidgrooves for bodily ejection from the window opening.

5. The combination recited in claim 4 which further includes resilientgasket means disposed between said window stop surfaces and the marginalportions of said panel adjacent thereto, said gasket means beingdeformable by pressure exerted thereon by said panel marginal portionsduring normal gaseous pressure conditions to thereby seal the spacebetween said panel and said window stop surfaces.

6. In a wall having a pair of spaced apart and parallel frame meanspartially defining a window opening and having further frame meansproviding spaced apart window stop surfaces defining the remainder ofthe window opening, a pressure venting window assembly for said openingincluding in combination, window stop means mounted along each of saidparallel frame mean and including a resiliently flexible portion havinga groove therein disposed on the side thereof facing the outer side ofthe wall, a non-fragible window panel dimensioned to close said windowopening and having a pair of spacedapart edge portions each received inone of said grooves to thereby retain said panel in the window openingwith marginal portions thereof adjacent said window stop surfaces, saidresiliently flexible portion of said stop means being movable to permitmovement of said edge portions of said panel while being retained insaid grooves whereby said panel is movable in response to abnormalgaseous pressures of less than a predetermined blow-out value actingagainst the inner face of the panel to thereby rapidly relieve saidpressure via the space created by such panel movement between saidwindow stop surfaces and the marginal portions of said panel adjacentthereto without thereby ejecting the panel from the window opening,resilient gasket means disposed between said window stop surfaces andthe marginal portions of said panel 9 adjacent thereto, said gasketmean-s being deformable by pressure exerted thereon by said panelmarginal portions during normal gaseous pressure conditions to therebyseal the space between said panel and said window stop surfaces, saidgasket means including bulbous portions each having a hollow crosssection when in the relaxed condition thereof and being disposed forresilient deformation by said panel to provide a flexible seal betweenthe panel marginal portions andthe window stop surfaces respectivelyadjacent thereto.

7. The combination recited in claim 6 wherein said window stop surfacescomprise a pair of shoulders each having an edge overlapped by saidpanel, said gasket means being positioned relative to each of saidshoulders so that a portion of each bulbous portion thereof is squeezedtogether between the panel and shoulder in the normal condition of thepanel While the remainder of each bulbous portion extends inwardly ofsaid shoulder edge so as to provide a hollow section which overlays suchedge whereby slightly superatmospheric pressures tend to urge theremaining hollow section of said bulbous portion against the shoulderedge to thereby obtain a self-sealing action against such pressures inthe window opening.

8. The combination recited in claim 7 wherein said gasket meanscomprises an endless loop having a solid grooved portion adapted toreceive the peripheral edges of said panel therein to thereby retainsaid gasket loop on said panel, said solid portion of said gasket loopbeing dimensioned to be received together with said bulbous portion insaid grooves in said flexible portions of said window stop means with africtional fit for retaining said panel in said stop means againstpressures below said predetermined blow-out value.

9. An explosion venting Wall construction including in combination, awall section having a pair of window openings therein spaced apart by arib portion thereof, said rib portion having a shoulder formed in eachof the surfaces thereof disposed in said window openings, each shoulderbeing located intermediate the inner and outer sides of said wallsection and facing the outer side of said wall section, a resilientwindow stop shaped and dimensioned so as to embrace the surfaces of saidrib portion disposed between said shoulders and on the inner side of thewall section, said window stop having a pair of spaced-apart grippingportions with one portion positioned for resiliently engaging one ofsaid shoulders of said rib portion and the other portion the othershoulder to thereby retain said stop in place on said rib portion, saidgripping portions of said Window stop each having a groove in the sidethereof facing the outer side of the wall section, and a pair of closurepanels formed of a non-fragile material and each dimensioned to closeone of said window openings, each of said panels having an edge portionretained in said groove of said gripping portion disposed in the samewindow opening as said panel, and means engaging the edges of saidpanels opposite said edges thereof retained in said grooves to therebyretain the panels in the window opening whereby upon the application ofabnormal pressure to the inner face of the panels said gripping portionsof said window stops flex away from said shoulders to permit outwardmovement of said panels without releasing the same to thereby permitventing of gaseous pressure around those edges of the panels extendingbetween the retained edges thereof.

10. The combination recited in claim 9 wherein said panels are formed insheets of resilient material and are held in an outwardly bowed convexshape in the window opening so that the flexing tension of the bowedpanel as it tends to straighten out urges said gripping portions of saidresilient stops against said rib portion so that said window stop andsaid panel provide retention for one another in the window opening.

11. The combination recited in claim 9 wherein said resilient windowstop comprises an extruded member having a back wall, a pair of spacedapart side walls extending from one side of said back wall and a pair ofleg walls extending from the inner sides of said side walls, theresiliency of said window stop tending to urge said leg walls toward theback wall thereof so that said window stop provides a clamping tensionagainst the surfaces of said rib portion.

12. The combination recited in claim 9 wherein said resilient windowstop comprises a member having a back wall, a pair of spaced apart sidewalls connected to said back wall and a pair of leg walls one connectedto each of said side walls and forming said gripping portions, theresiliency of said window stop tending to urge said leg walls toward theback wall so that said window stop provides a clamping tension againstthe surfaces of said rib portion.

13. An explosion venting window assembly comprising a metal window sashhaving a pair of flanges at opposite edges of a window opening thereinwhich extend towards one another in the plane of the window opening, apair of gaskets each having a portion engaging one of said flanges ofthe sash to retain said gaskets thereon, each gasket including aresilient portion having a groove therein disposed on the outer side ofsaid flanges, said resilient portion having a flexible connection withsaid portion of said gasket engaging said sash flange to permit movementof said gasket portions relative to one another, and a closure panelformed of non-fragile material dimensioned to close the window openingand having a pair of opposite edge portions received in the grooves ofsaid resilient portions of said gaskets for retaining said closure panelagainst the sash in the window opening under normal pressure conditions,said grooved resilient portions of said gaskets being flexed outwardlytherefrom with outward movement of said panel in response to theapplication of abnormal pressures of less than a predetermined blow-outpressure to the inner face of the panel so that said panel pulls awayfrom the sides of the sash extending between said gaskets to provideopenings between the last mentioned sides of the sash and panel forrelieving said abnormal pressures, said resilient portion of each gasketbeing adapted to grip the panel edge portion received therein withsufficient force to retain said panel in said groove until the panel issubjected to the predetermined blow-out pressure whereupon the panel ispulled out of said grooves for bodily ejection from the window opening.

14. The combination recited in claim 13 wherein said window sashincludes a second pair of flanges extending between said first mentionedflanges along said last mentioned sides of the sash, and which furtherincludes additional gaskets extending between said first mentionedgaskets, each of said gaskets having a groove therein adapted to receiveone of said flanges of the window sash to retain said gaskets thereon inthe window opening.

15. The combination recited in claim 14 wherein said additional gasketseach include a bulbous portion resiliently deformable by the panel froma hollow, relaxed cross-sectional shape to a flattened section forsealing the pressure relieving openings between said panel and sashunder normal pressure conditions.

16. The combination recited in claim 15 wherein said additional gasketsare joined to said first mentioned gaskets to provide a one piece gasketassembly providing a peripherally continuous weather seal between saidpanel and sash.

17. In a building having a wall provided with a frame defining a Windowopening therein, a panel closing said window opening, a weather stripdisposed along each edge of a pair of opposite edges of said frame, saidstrips each comprising a first portion secured to said frame and asecond portion having a resilient hinge connection to said firstportion, said second portion being resilient and having a groove thereinreceiving and gripping an edge 1 ll portion of the panel to therebyretain the panel in the Window opening, said hinge connections of saidfirst and second portions of each strip permitting movement of saidpanel in an outward direction while being retained in said grooves inresponse to abnormal fluid pressure of less than a predeterminedblow-out value acting outwardly on the inner face of the panel, such asmight result from a minor explosion within the building, to therebyprovide a pressure venting opening between the frame and those edges ofthe panel disposed between said pair of opposite edges of said frame,said second portions of said strips retaining said panel edges in saidgrooves against fluid pressures less than the predetermined blow-outpressure acting outwardly on the inner face of the panel and releasingsaid panel edges in response to higher pressures.

References Cited in the file of this patent UNITED STATES PATENTS1,959,643 Plym May 22, 1934 2,352,727 McMahon July 4, 1944 2,641,031Ehret June 9, 1953 2,736,402 Hicks Feb. 28, 1956

1. IN A BUILDING HAVING A WINDOW OPENING THEREIN PROVIDED WITH AT LEASTTWO PAIRS OF OPPOSITE EDGES, THE COMBINATION OF A WINDOW PANEL CLOSINGSAID OPENING, A PAIR OF PANEL ENGAGING MEMBERS EXTENDING ALONG A FIRSTPAIR OF CORRESPONDING OPPOSITE EDGES OF THE WINDOW OPENING AND THEPANEL, SAID PANEL ENGAGING MEMBERS HAVING EACH A FIRST PORTION SECURELYATTACHED TO THE FIRST PAIR OF EDGES OF THE WINDOW OPENING AND ARESILIENT SECOND PORTION MOVABLY CONNECTED TO SAID FIRST PORTION ANDHAVING A GROOVE THEREIN FOR RECEIVING THE CORRESPONDING EDGE OF THEPANEL, SAID SECOND PORTIONS OF SAID PANEL ENGAGING MEMBERS NORMALLYRETAINING THE PANEL AGAINST THE SECOND PAIR OF EDGES OF THE WINDOWOPENING BUT BEING MOVABLE RELATIVE TO SAID FIRST PAIR OF EDGES OF THEWINDOW OPENING IN A DIRECTION OUTWARDLY OF THE WINDOW OPENING WHILERETAINING SAID OPPOSITE EDGES OF THE PANEL IN GRIPPED RELATION IN SAIDGROOVES TO PERMIT THE PANEL TO MOVE BODILY OUTWARDLY AWAY FROM SAIDSECOND PAIR OF WINDOW EDGES, SAID SECOND PORTIONS BEING SUFFICIENTLYDISTORTABLE TO RELEASE THE EDGE OF THE PANEL FROM SAID GROOVE INRESPONSE TO AN ABNORMALLY HIGH PRESSURE ACTING OUTWARDLY AGAINST THEINNER FACE OF THE PANEL.